Trailer tow mirror

ABSTRACT

A mirror assembly has a pair of telescoping tubular supports extending between a support base and a mirror head to provide adjustment of the mirror head toward and away from the support base. Friction shoes within the tubular supports releasably hold such supports against unintentional telescoping movement. Cooperating stops on the telescoping supports limit outward movement of the mirror head and prevent complete separation of the telescoping supports. The tubular supports are hingedly attached to the support base for rotation about a vertical axis, and cooperating detents and spring elements on the supports and support base releasably hold the supports against rotation.

REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. Ser. No. 10/191,264filed Jul. 8, 2002 which is a continuation of U.S. Ser. No. 09/900,296,filed Jul. 6, 2001, now U.S. Pat. No. 6,416,192 which is a continuationof U.S. Ser. No. 09/399,293 filed Sep. 17, 1999, now U.S. Pat. No.6,276,805.

BACKGROUND OF THE INVENTION

[0002] This application relates to the art of vehicle rear view mirrorsand, more particularly, to trailer tow mirrors that can be adjusted toextend varying distances outwardly from the side of a vehicle.

[0003] Telescoping trailer tow mirror assemblies desirably aremaintained in their adjusted position against unintentional movement. Atthe same time, it is desirable that adjustment can be performed quicklywithout the need for the use of tools or complicated mechanisms. Inaddition, it is desirable that the mirror assembly be rotatable about avertical axis relative to a support base in response to forward orrearward forces acting on the mirror head. This minimizes damage to themirror assembly when a fixed object is struck by the mirror head or bythe telescoping support arms.

SUMMARY OF THE INVENTION

[0004] A telescoping trailer tow mirror assembly has a support base witha pair of vertically-spaced parallel tubular support arms extendinghorizontally outwardly therefrom. A pair of vertically-spaced parallelmirror mounting arms are telescopically received within the tubularsupport arms for longitudinal movement relative thereto to vary thedistance between the support base and a mirror head carried by themounting arms.

[0005] In accordance with the present application, releasable holdingdevices are located internally of the tubular support arms forreleasably holding the mounting arms against longitudinal movementrelative to the support arms. In one arrangement, the releasable holdingdevices are friction shoes carried by the mounting arms and are biasedinto engagement with internal surfaces of the tubular support arms.

[0006] In a preferred arrangement, each mounting arm carries twolongitudinally-spaced friction shoes that engage an inner surface of atubular support arm in which a mounting arm is received to provideimproved stability and vibration performance, along with betteradjustment feel.

[0007] In accordance with another aspect of the application, the supportarms are hingedly connected to the support base for rotation about avertical axis. Cooperating detents and spring elements adjacent to thehinged connections releasably hold the support arms againstunintentional rotation. When a forward or rearward force is applied tothe mirror head or support arms, the spring elements are cammed out ofboth the upper and lower detents to permit rotation of the support armsrelative to the support base and minimize or prevent damage to themirror assembly or vehicle.

[0008] The horizontally extending and vertically-spaced paralleltelescoping supports of the present application provide excellentstability during telescoping movement. Location of the friction shoesinternally of the tubular support arms hides any wear marks that mayresult from repeated telescoping adjustments.

[0009] It is a principal object of the present invention to provide animproved telescoping trailer tow mirror assembly.

[0010] It is also an object of the invention to provide a telescopingtrailer tow mirror assembly that has very good stability duringtelescoping adjustment.

[0011] It is another object of the invention to provide a telescopingtrailer tow mirror assembly with friction shoes that releasably hold thetelescoping supports in an adjusted position against unintentionalmovement.

[0012] It is a further object of the invention to provide an adjustablesupport for a mirror head wherein a mounting arm that is slidablyreceived in a tubular support arm carries a pair oflongitudinally-spaced friction shoes that are biased into engagementwith the inner surface of the support arm for releasably holding themounting arm against sliding movement.

[0013] It is an additional object of the invention to provide atelescoping trailer tow mirror assembly that requires no tools orspecial fittings for adjustability and that can be adjusted veryquickly.

[0014] It is also an object of the invention to provide an improveddetent and spring element arrangement for releasably holding supportarms against rotation about a vertical axis relative to a support base.

BRIEF DESCRIPTION OF THE DRAWING

[0015]FIG. 1 is a perspective illustration of a telescoping trailer towmirror assembly constructed in accordance with the present application;

[0016]FIG. 2 is an exploded perspective illustration thereof;

[0017]FIG. 3 is a rear perspective illustration of a base plate usedwith the assembly of FIGS. 1 and 2;

[0018]FIG. 4 is a front perspective illustration thereof;

[0019]FIG. 5 is a perspective illustration of a friction shoe used withthe assembly of FIGS. 1 and 2;

[0020]FIG. 6 is a partial cross-sectional plan view showing the frictionshoe of FIG. 5 in an installed position;

[0021]FIG. 7 is a partial perspective illustration showing a stop forthe friction shoe to prevent complete displacement of a mounting armfrom within a support tube;

[0022]FIG. 8 is a rear elevational view of a support base that isadapted to be attached to a vehicle;

[0023]FIG. 9 is a side elevational view taken generally on line 9-9 ofFIG. 8;

[0024]FIG. 10 is a partial cross-sectional elevational view taken online 10-10 of FIG. 9 with portions omitted for clarity of illustrationand showing detent members on tubular support arms cooperating withspring rods;

[0025]FIG. 11 is a partial perspective illustration showing the detentmembers and torsion rods of FIGS. 8-10;

[0026]FIG. 12 is a partial perspective illustration showing detents onsupport arms cooperating with a single spring rod;

[0027]FIG. 13 is a partial perspective illustration of a preferredembodiment for the mounting arms, support tubes and friction shoes;

[0028]FIG. 14 is a perspective illustration of a support tube and aspring clip that attaches to the tube to provide a stop;

[0029]FIG. 15 is a perspective illustration of a friction shoe used inthe preferred embodiment of FIG. 13;

[0030]FIG. 16 is a cross-sectional view similar to FIG. 6 but showingthe preferred embodiment of FIG. 13;

[0031]FIG. 17 is a top plan view of one of the mounting arms thatextends outwardly from the base of FIG. 13; and

[0032]FIG. 18 is a cross-sectional elevational view taken generally online 18-18 of FIG. 17, and with a friction shoe of FIG. 15 added to showhow a shoe is received in a mounting arm.

DESCRIPTION OF A PREFERRED EMBODIMENT

[0033] Referring now to the drawing, wherein the showings are forpurposes of illustrating a preferred embodiment of the invention onlyand not for purposes of limiting same, FIG. 1 shows a support A that isadapted to be attached externally of a vehicle body. Support A includesa support base 10 having an escutcheon 12 attached to the outer sidethereof.

[0034] A pair of horizontally extending parallel tubular support arms14, 16 are vertically spaced-apart and have end portions 18, 20 hingedlyconnected to support A by way of an upper clevis 24 and a lower clevis26 for rotation about a vertical axis 28.

[0035] Mirror head assembly B is attached to tubular support arms 14, 16for selective adjustable movement toward and away from support A, andthe mirror head assembly B includes a mirror base 30 and a mirrorescutcheon 32. Each tubular support arm 14, 16 has a pair of oppositeinwardly extending flexible stop tabs 14 a, 14 b and 16 a, 16 b adjacentthe outer ends thereof for cooperating with abutments provided by stopprojections on mirror head assembly B as hereinafter described.

[0036]FIG. 2 shows a mirror base plate C having a mounting portion 40that is assembled to and between the rear of mirror base 30 and theinterior of mirror escutcheon 32 by suitable fasteners. A pair ofvertically-spaced parallel mounting arms 42, 44 extend horizontally frommounting portion 40 through openings 46, 48 in mirror escutcheon 32 forreception in tubular support arms 14, 16. The free end portions oftubular support arms 14, 16 are longitudinally notched or cut-away asindicated at 50, 52 along the sides thereof that face toward mountingportion 40 so that the notched end portions of the support arms can movelongitudinally behind mounting portion 40 along mounting arms 42, 44instead of striking the forward edge thereof. Primary and secondarymirrors 56, 58 are mountable to mirror base 30 in a known manner.

[0037] With reference to FIGS. 3 and 4, tubular mounting arms 42, 44have outwardly curved front portions 62, 64 and flat rear web portions66, 68. Parallel flat sidewalls 70, 72 on mounting arm 42 extend betweencurved front portion 62 and rear web portion 66. Flat sidewalls 70, 72project rearwardly beyond rear web portion 66 as generally indicated at70 a, 72 a. Mounting arm 44 has flat parallel sidewalls 80, 82 extendingbetween front outwardly curved portion 64 and flat rear web portion 68.Flat sidewalls 80, 82 extend rearwardly beyond flat web portion 68 asindicated at 80 a, 82 a.

[0038] Opposite inclined projections 90, 92 on the outer surfaces offlat sidewalls 70, 72 of mounting arm 42 provide inclined ramps that camflexible tabs 14 a, 14 b on tubular support arm 14 outwardly to ridepast the projections when mounting arm 42 is telescoped inside ofsupport arm 14 during initial assembly. Tabs 14 a, 14 b then snapinwardly and cooperate with end stops or abutments 90 a, 92 a onprojections 90, 92 to limit outward movement of mirror head assembly Band prevent separation of mounting arm 42 from support arm 14. Mountingarm 44 has opposite inclined projections 94, 96 with end stops orabutments 94 a, 96 a that cooperate with tabs 16 a, 16 b on tubularsupport arm 16 in the same manner. A tool may be used to release thetabs from engaging the end stops when it is desired to separate themounting arms from the support arms for repair or replacement purposes.

[0039] Each mounting arm 42, 44 has a generally rectangular opening 102,104 in curved front wall 62, 64 thereof closely adjacent the free end ofthe arm. A pair of longitudinally-spaced holes 106, 108 are provided inflat rear web portion 66 of mounting arm 42 opposite from opening 102,along with corresponding holes 110, 112 in rear web portion 68 ofmounting arm 44 opposite from opening 104. These openings and holes arefor use in connection with friction shoe members as will be describedwith reference to FIG. 5.

[0040] In FIGS. 5-7, friction shoe D includes an enlarged head portion120 having a curved outer surface that is curved at approximately thesame curvature as the interior surfaces of tubular support arms 14, 16.Friction shoe D has a pair of spaced-apart rearwardly projecting arms122, 124 with barbed end portions 126, 128. A central guide projection130 extends rearwardly from head 120 between arms 122, 124 for receivinga coil spring 132 as shown in FIG. 2.

[0041] A friction shoe D is insertable through opening 102 in mountingarm 42, with arms 122, 124 being inserted first so that barbed endportions 126, 128 snap through holes 106, 108 in rear web 66. Thisattaches spring 132 and friction shoe D to mounting arm 42 for holdingsame in position during initial assembly of mounting arm 42 withintubular support arm 14. Friction shoe D is depressed inwardly againstthe biasing force of spring 132 to allow the shoe to be received withinsupport arm 14 along with mounting arm 42.

[0042] The spacing between friction shoe arms 122, 124 and the spacingbetween holes 106, 108 are such that the arms are spring loaded whenthey are inserted into the holes so that there will be no relativemovement between a friction shoe and a mounting arm in a directionparallel to the longitudinal axis or length of the mounting arm.

[0043] After assembly of the mounting arms within the tubular supportarms, engagement of the friction shoe with the inner surface of tubularsupport arm 14 compresses spring 132 so that barbs 126, 128 projectfreely beyond web 66 into the space between extensions 70 a, 72 a ofsidewalls 70, 72. The dimensions of friction shoe arms 122, 124 relativeto holes 106, 108 and 110, 112 are such as to permit movement of thearms relative to the holes in a direction that is parallel to the lengthof the arms. This allows a friction shoe to move relative to itsmounting arm in a direction that is perpendicular to the length of themounting arm so that a spring 132 biases the shoe into engagement withthe inner surface of a support tube. A similar friction shoe D isassembled in the same manner to mounting arm 44.

[0044] The coil springs bear against rear web portion 66 or 68 to biasthe outer curved surface on head 120 of friction shoes D through opening102 or 104 into engagement with the inner surfaces of tubular supportarms 14, 16. This permits longitudinal sliding adjustment of mountingarms 42, 44 relative to tubular support arms 14, 16 while releasablyholding the mounting arms in a desired adjusted position againstlongitudinal movement relative to support arms 14, 16.

[0045] With reference to FIGS. 8-11, a pair of spring elements or rods140, 142 are attached to the rear of support base 10 by a clamp 144.Spring rod 142 has an upper end portion 142 a that extends through ahole 181 in support base 10 and cooperates with an axially extendingdetent 160 in the outer periphery of a detent member 161 on mountingportion 18 of support arm 14. This normally holds support arm 14 in theposition shown in FIG. 1 extending straight out from support A. Whenforward or rearward horizontal force is applied to mirror assembly B,detent 160 resiliently cams upper end portion 142 a of spring rod 142outwardly onto the outer circumferential surface of detent member 161 topermit rotation of support arm 14 about vertical axis 28 relative tosupport base 10. Hole 181 is oblong as shown in FIG. 9 in a directionaway from the outer periphery of detent member 161 to permit movement ofspring rod end portion 142 a away from detent member 161 when endportion 142 a moves out of detent 160 and onto the outer periphery ofdetent member 161. Spring rod 140 has a lower end portion 140 a thatcooperates with a detent 170 in a detent member 171 on mounting portion20 of support arm 16 in the same manner. More specific descriptions andillustrations of the detents and their manner of operation may be foundin U.S. Pat. No. 5,841,594 issued Nov. 24, 1998, to Rothe. The Rothepatent is assigned to the same assignee as the present application andthe disclosure of the patent hereby is incorporated herein by reference.

[0046] In the arrangement of FIG. 12, a single spring rod 180 hasopposite end portions 180 a, 180 b cooperating with detents 160, 170 toreleasably hold support arms 14, 16 against rotation. When asufficiently large force is applied to arms 14, 16, spring rod endportions 180 a, 180 b yield as they are cammed out of detents 160, 170to ride on the periphery of detent members 161, 171. This permitsrotation of the support arms about a vertical axis 28 for movement ofthe mirror assembly toward the vehicle.

[0047] In the arrangement of the present application, it will berecognized that friction shoe D defines a releasable holding device thatis located completely internally of the tubular support arms forreleasably holding the telescoping mounting arms against unintentionallongitudinal movement relative to the tubular support arms. Grasping ofthe mirror head assembly in a person's hands and applying force towardor away from the support base overcomes the frictional resistance of thefriction shoes to enable variation in the distance between the mirrorhead and the support base. Mounting arms 42, 44 are generally tubular asillustrated in the drawings. The spring rods also may be referred to astorsion rods, or as resilient or yieldable elements.

[0048]FIG. 13 shows a preferred embodiment that includes a base plate Ehaving a pair of integral spaced-apart parallel mounting arms 210 and212 extending outwardly therefrom. Each mounting arm 210, 212 has across-sectional shape that is similar to that of mounting arms 42, 44 inFIG. 4. Thus, each mounting arm 210, 212 has an arcuate outer surface214, 216 that is transversely curved to generally correspond with theinner transverse curvature of a support tube that receives a mountingarm. Mounting arm 210 has a pair of longitudinally-spaced openings 220,222 in arcuate outer surface 214 thereof. Mounting arm 212 has acorresponding pair of openings, only one of which is shown at 224 inFIG. 13 and the other of which is shown at 226 in FIG. 16. Arcuatesurfaces 214, 216 are cut-away adjacent to base plate E as indicated at230, 232 to provide generally vertical abutment surfaces 234, 236. Thecross-sectional size and shape of the mounting arms is such that theyare closely received in the tubular support arms while beinglongitudinally movable relative thereto.

[0049] Each of mounting arms 210 and 212 is received in a support tube,only one of which is shown at F in FIGS. 13 and 14. The lower endportion of support tube F is cut-away as indicated at 240 to allow theupper portion of the support arm to extend over baseplate E. Atransverse opening 242 is provided in support arm F spaced inwardly frominner end 244 thereof for receiving a stop portion of a clip asdescribed hereafter. A pair of opposite notches 246, 248 are provided inalignment with opening 242 for attaching the stop clip to the tubularsupport arm.

[0050] A generally U-shaped spring clip G has a pair of spaced-apartlegs 250, 252 connected by a base portion 254 that defines a stop forpreventing removal of a mounting arm from within a tubular support arm.Legs 250, 252 are bent to provide inwardly extending detents 258, 260located intermediate the ends of legs 250, 252 and the base portion 254.

[0051] Subsequent to insertion of a mounting arm into a support arm, asshown by way of example for mounting arm 212 and support arm F in FIG.13, spring clip G is positioned with legs 250, 252 thereof straddlingsupport tube F and is then pushed downwardly until detents 258, 260 snapinto notches 246, 148. In this position, base portion 254 extends acrossopening 242 and rests against the opposite bottom side edges thereof asshown in FIG. 13 to provide a stop that is engageable by abutmentsurface 236 to prevent complete displacement of mounting arm 212 fromwithin support arm F. A corresponding clip and end stop arrangement isprovided for mounting arm 210 and its support tube.

[0052]FIG. 15 shows a friction shoe H having an arcuate outer frictionsurface 280 that is not curved at a constant radius because the frictionshoe does not run on the centerline of the support tube, and thefriction shoe must be symmetrical for use on both left and right mirrorassemblies. Transverse grooves 282, 284 are provided in friction surface280 adjacent flat side 286 thereof for transporting dirt or foreignmaterial away from the interface between the friction surface of afriction shoe and the inner surface of a tubular support arm. Thegrooves also reduce the contact area of a shoe friction surface toprovide a higher unit force of engagement between a friction surface andthe inner surface of a tubular support arm. The grooves also reduce theamount of plastic material used to mold the friction shoes.Corresponding groves are provided in friction surface 280 adjacent theopposite flat surface 288.

[0053] The curvature of an outer friction surface 280 relative to thecurved outer surface 216 of a mounting arm 212 is illustrated in FIG.18. Because the curvature of mounting arm outer surface 216 isapproximately the same as the curvature of the inner surface of atubular support arm F, this also illustrates the approximate curvatureof friction surface 280 relative to the curvature of the inner surfaceof a tubular support arm. Thus, it is only the outer apex portion of afriction surface 280 that engages the inner surface of a tubular supportarm. A friction shoe usually is inclined to the vertical up to about 3°when it is within a tubular support arm. The inclination will be eitherto the right or to the left depending on whether it is the right or leftmirror assembly.

[0054] Longitudinal ribs 290, 292 project outwardly from opposite sideflat surfaces 286, 288 as shown in FIG. 15. A guide stem 296 includes apair of spaced-apart arms 302, 304 having barbed end portions 306, 308that snap through openings 310, 312 in mounting arm 212 as shown in FIG.16. Prior to snapping the barbed arms 302, 304 through openings 310,312, coil springs 320, 322 are positioned over the arms. The length ofthe springs relative to the arms is such that friction shoes H areoutwardly biased so that friction shoes 280 engage the inner surface ofa tubular support arm.

[0055] The enlarged head of friction shoe H has an opening 324therethrough. When a friction shoe is positioned within a mounting arm,opening 324 extends in the direction of the longitudinal axis of themounting arm. A rounded projection 326 that is shown in FIGS. 16 and 18projects into the top of opening 324 on the opposite side of frictionsurface 280. Electrical wires may extend through the mounting andsupport arms, and through openings 324 in friction shoes H for supplyingpower to a motorized adjustment or a defrosting device in the mirrorhead. Rounded projections 326 in the friction shoe openings help toprevent abrasion or pinching of the wires in the gap between mountingarm openings 224, 226 and the heads of friction shoes H.

[0056]FIG. 17 shows mounting arm 212 as having internal sidewallsurfaces 340, 342 that converge in a direction inwardly of the mountingarm from open terminal end 344 thereof. This slope on the internalsidewall surfaces enables a core pull from open end 344 when the baseplate and its integral mounting arms are molded of plastic material. Inview of this convergence of the interior sidewall surfaces, the body orenlarged head of friction shoe H is reduced in width across flat sides286, 288 thereof. The reduced width of the enlarged head allows the headto be received within areas of reduced width between sidewall innersurfaces 340, 342.

[0057] As shown in FIG. 18, opening 226 in mounting arm 212 is made withopening sidewalls 350, 352 that are spaced-apart a greater distance thaninner sidewall surfaces 340, 342 of mounting arm 212. The spacing ofopening sidewalls 350, 352 is the same for both of openings 226 and 224.Opening sidewalls 350, 352 intersect inwardly extending horizontalshoulders 354, 356 that in turn intersect inner sidewall surfaces 342,340. Longitudinal guide ribs 290, 292 on friction shoe H are relativelyclosely received between opening sidewalls 350, 352 for guiding movementthereof and providing lateral stability for the friction shoe.

[0058] The depth of opening sidewalls 350, 352 is such as to enabledepression of a friction shoe H downwardly for snapping the barbed endsof guide stem arms 302, 304 through a mounting arm opening 312. Coilspring 320 then acts against the bottom wall of mounting arm 212 and theunderside of the enlarged head on friction shoe H for biasing frictionshoe H upwardly in FIG. 18. When a mounting arm is received within asupport arm, spring 320 is compressed and the barbed ends of guide stemarms 302, 304 are spaced slightly from the outer bottom surface ofmounting arm 212.

[0059] Although the invention has been shown and described withreference to a preferred embodiment, it is obvious that equivalentalterations and modifications will occur to others skilled in the artupon the reading and understanding of this specification. The presentinvention includes all such equivalent alterations and modifications,and is limited only by the scope of the claims.

We claim:
 1. In a vehicle rear view mirror assembly, a support basehaving a pair of spaced-apart parallel support tubes extending outwardlytherefrom, a mirror head having a pair of spaced-apart parallel mountingarms extending outwardly therefrom, said mounting arms being slidablyreceived within said support tubes to support said mirror head on saidsupport base and provide selective adjustable movement of said mirrorhead toward and away from said support base, and at least one of saidmounting arms having a releasable holding device carried therebyinternally of the said support tube in which it is received toreleasably hold said mounting arms in a desired adjusted positionagainst longitudinal movement relative to said support tubes.
 2. Themirror assembly of claim 1 wherein said support tubes have tube innersurfaces and said releasable holding device comprises a friction shoehaving a friction surface engaging said tube inner surface of saidsupport tube in which said one mounting arm is received.
 3. The mirrorof claim 2 wherein said friction shoe is biased in a direction to engagesaid friction surface with said tube inner surface of said support tubein which said one mounting arm is received.
 4. The mirror assembly ofclaim 3 wherein said mounting arms are tubular and said friction shoe iscarried internally of said one mounting arm, and said one mounting armhaving an opening therein through which said friction shoe projects toengage said friction surface with said tube inner surface of saidsupport tube in which said one mounting member is received.
 5. Themirror assembly of claim 1 wherein said releasable holding devicecomprises a pair of releasable holding devices spaced-apartlongitudinally of said one mounting arm.
 6. The mirror assembly of claim5 wherein said support tube in which said one mounting member isreceived has a tube inner surface and said pair of releasable holdingdevices comprise friction shoes having friction surfaces engaging saidtube inner surface.
 7. The mirror assembly of claim 1 wherein both ofsaid mounting arms have a releasable holding device carried thereby. 8.The mirror assembly of claim 7 wherein each of said mounting arms has apair of said releasable holding devices carried thereby, and said pairof said releasable holding devices on each of said mounting arms arespaced longitudinally of said mounting arms.
 9. The mirror assembly ofclaim 8 wherein all of said releasable holding devices comprise frictionshoes having friction surfaces and said support tubes have innersurfaces engaged by said friction surfaces.
 10. The mirror assembly ofclaim 9 wherein said friction shoes are yieldably biased in a directionto engage said friction surfaces with said inner surfaces of saidsupport tubes.
 11. The mirror assembly of claim 1 wherein said supporttubes have open ends through which said mounting arms extend, at leastone of said pair of support tubes having at least one stop thereonadjacent said open end thereof for cooperation with an abutment on atleast one of said mounting arms to prevent separation of said arms fromsaid tubes.
 12. The mirror assembly of claim 1 wherein said supporttubes have open ends through which said mounting arms extend, said tubeshaving stops thereon adjacent said open ends thereof, and said mountingarms having abutments thereon for cooperation with said stops to preventremoval of said arms from within said tubes.
 13. The mirror assembly ofclaim 12 wherein said stops are on spring clips attached to said supporttubes subsequent to insertion of said mounting arms into said supporttubes.
 14. The mirror assembly of claim 1 wherein said releasableholding device comprises a friction shoe carried by said mounting armfor transverse movement relative thereto, and a spring biasing saidfriction shoe in a direction for cooperation with said tubular supportto prevent relative longitudinal movement between said mounting arm andtubular support.
 15. The mirror assembly of claim 1 wherein said supporttubes are attached to said support base by hinged connections forrotation about a common vertical axis, and releasable detent devicesbetween each of said support tubes and said support base adjacent saidhinged connections to releasably hold said support tubes againstrotation about said vertical axis when said detent devices are engagedand to permit such rotation when said detent devices are released. 16.The mirror assembly of claim 15 wherein said detent devices comprise adetent in each of said support tubes adjacent said hinged connectionsand a resilient element on said support base releasably received in eachsaid detent.
 17. The mirror assembly of claim 16 wherein said resilientelement comprises a separate resilient element for each said detent. 18.In a rear view mirror assembly, a support base having an elongatedtubular support arm extending outwardly therefrom, a mirror head havingan elongated mounting arm extending outwardly therefrom, said mountingarm being slidably received in said support arm to support said mirrorhead on said support base and provide selective adjustment of saidmirror head toward and away from said support base, a friction devicecarried by said support arm internally of said support arm, saidfriction device having an outer friction surface and said support armhaving an inner surface engaged by said friction surface, and saidfriction device being yieldably biased in a direction to engage saidfriction surface with said inner surface of said support arm toreleasably hold said mounting arm in a desired adjusted position againstlongitudinal movement relative to said support arm.
 19. The mirrorassembly of claim 18 wherein said friction device comprises a pair offriction shoes spaced from one another longitudinally of said mountingarm.
 20. The mirror assembly of claim 18 wherein said friction devicecomprises a friction shoe having a friction shoe head, a barbed guidestem extending from said head and having a barbed end portion, and saidmounting arm having an opening therein through which said barbed endportion is snapped to attach said friction shoe to said mounting arm.21. The mirror assembly of claim 20 wherein said head has a frictionsurface on the opposite side thereof from said guide stem, and a coilspring surrounding said guide stem for biasing said head in a directionto engage said friction surface with said inner surface of said tube.22. The mirror assembly of claim 18 wherein said support base has a pairof elongated parallel tubular support arms extending outwardly therefromand said mirror head has a pair of elongated parallel mounting armsextending outwardly therefrom and being slidably received in said pairof tubular support arms, and each of said mounting arms having a saidfriction device carried thereby.
 23. The mirror assembly of claim 22wherein said friction device carried by each of said mounting armscomprises a pair of friction devices spaced-apart longitudinally of saidmounting arms.
 24. The mirror assembly of claim 23 wherein said mountingarms are tubular and each of said pair of friction devices comprisefriction shoes carried by said mounting arms internally thereof, andsaid mounting arms having openings therein through which said frictionshoes extend into engagement with inner surfaces of said support arms.25. The mirror assembly of claim 24 wherein said friction shoes haveguide stems attached to said mounting arms for movement of said frictionshoes relative to said mounting arms longitudinally of said guide stems,and biasing devices positioned between said mounting arms and saidfriction shoes to bias said friction shoes into engagement with innersurfaces of said support arms.
 26. A telescoping trailer tow mirrorassembly having a support base and a mirror head, cooperatingtelescoping mounting and support tubes extending between said supportbase and said mirror head for supporting said mirror head on saidsupport base and for providing adjustable movement of said mirror headtoward and away from said base, and a releasable holding deviceinternally of said tubes for releasably holding said tubes againstmovement relative to one another.
 27. The mirror assembly of claim 26wherein said support tube is attached to said support base and saidmounting tube is attached to said mirror head, and said mounting tubebeing received in said support tube.
 28. The mirror assembly of claim 27wherein said releasable holding device is carried by said mounting arm.29. The mirror assembly of claim 28 wherein said mounting arms extendalong a longitudinal tube axis and said support tube has an innersurface, said releasable holding device comprising a friction shoebiased into engagement with said inner surface transversely of said tubeaxis.
 30. The mirror assembly of claim 26 wherein said releasableholding device comprises a pair of friction shoes spaced-apartlongitudinally of said tubes.
 31. The mirror assembly of claim 28wherein said support tube is hinged to said support base for rotationabout a vertical axis, said support tube having a detent adjacent saidsupport base, and said support base having a spring rod releasablyreceived in said detent to releasably hold said support tube againstrotation.
 32. In a vehicle rear view mirror assembly including a supportbase having a pair of vertically-spaced parallel mirror support armsextending outwardly therefrom, said support arms being attached to saidsupport base by hinged connections for rotation about a vertical axis,each of said support arms having a detent adjacent to said hingedconnections, and a yieldable element releasably received in each of saiddetents for releasably holding said support arms against rotationrelative to said support base.
 33. The mirror assembly of claim 32wherein said hinged connections include support arm end portions havingouter peripheries spaced radially outwardly of said vertical axis, andsaid detents being in said outer peripheries.
 34. The mirror assembly ofclaim 33 wherein said yieldable element comprises a spring rod having aretaining portion thereof received in said detent, said retainingportion being movable out of said detent to permit rotation of saidsupport arm about said vertical axis.